1. Technical Field
The present invention relates to a polymer nanocapsule and a preparing method thereof, and more particularly a 3D covalent molecular network nanocapsule, and a preparing method thereof.
2. Description of the Related Art
A polymer nanocapsule, which is a particle having a wall made of a polymer and a hollow internal space, may be used to support and release various materials. Since a nanocapsule may be applied to various fields such as a drug delivery system (DDS), an external skin preparation, a catalyst, a fiber, and the like, research into the nanocapsule has been widely conducted.
Generally, in order to prepare the polymer nanocapsule, various methods such as synthesis using a template, self-assembly of an amphiphilic polymer, emulsion synthesis, removal of a core using dendrimer, and the like, are used. However, since most of the nanocapsules are not chemically cross-linked, the nanocapsule may be easily deformed or decomposed by an environmental change. Therefore, in order to preserve an original structure of the polymer nanocapsule under various conditions, it is important that the nanocapsule has a cross-linked structure. In this case, for the cross-linked structure, addition of a cross-linking agent is required, and a post-processing process such as a removal process of a template and a catalyst or a core is required, such that an additional time and a complicated process should be required.
Describing an example of applying the nanocapsule in detail, in a drug delivery system (DDS), as an injection formulation for delivering a poorly water soluble drug, a contrast agent, or the like, into cells or in a body, there are polymer micelles formed through self-assembly of an amphiphilic block copolymer, a liposome made of a phospholipid bilayer, and the like. These materials have been widely studied as a formulation for delivering various physiological active drugs in the body.
However, in the case of the polymer micelle and liposome, since structures thereof are maintained by non-covalent bonds, the polymer micelle and liposome may be dissociated into monomers having a low molecular weight while being diluted in the body. As the polymer micelle and liposome become physically unstable as described above, a drug encapsulated therein is not sufficiently delivered, and it is difficult to effectively use the drug.
In the external skin preparation, as a method for stabilizing a useful active material, a method of using a polymer nanocapsule has been widely studied. However, it is impossible to completely stabilize the active material only by simply capturing the useful active material in the polymer particles. Particularly, when these particles are used in a formulation such as cosmetics, the polymer may be swelled by water, a surfactant, oil, or the like, in the formulation, such that there is a difficulty in that unstable active material is slowly discharged to the outside and deformed for a long period of time.